Sonographic Evaluation of the Fetal Femur Length in the Chinese Population

Abstract

Sonograms of 128 Chinese fetuses scanned between 16-20 weeks' gestational age, with last menstrual period and average sonographic age corresponding by ± 10 days, were evaluated retrospectively. The fetal femur length was measured longitudinally using a linear phased array transducer. The observed femur lengths were compared with the corresponding data in Hadlock's chart, which is based on a white middle class population. Results indicated that the Chinese femur length was shorter than the Hadlock values by 0.56 mm. The analysis of variance revealed that this difference was consistent throughout pregnancy. Although the findings were statistically significant, they do not indicate a need for an adjustment to the Hadlock chart, as 0.56 mm would suggest a difference of only O.3 weeks.